8Reese's peanut butter cups (snack size)(chopped, plus extra for topping (Note 1))
1cupReese's Pieces candy(plus extra for topping)
In a mixing bowl, combine the flour, baking soda, baking powder, and salt. Whisk to combine. Set aside.
In the bowl of a stand mixer fitted with a paddle attachment, add the butter, granulated and dark brown sugars. Mix together until well combined and creamy, approx. 2 minutes. Add the eggs, one at a time, and the vanilla, mixing well after each addition.
Slowly add in the flour mixture, mixing until just combined. Scrap down the sides of the bowl if necessary.
Add the peanut butter cups and Reese's pieces to the dough. Fold together.
Using a 2-tablespoon cookie scoop, portion the dough onto a parchment-lined baking sheet. Chill for at least 20 minutes, or as much as 24 hours.
Preheat the oven to 375 degrees. Place the dough 2 inches apart on a parchment-lined baking sheet. Bake for 8-10 minutes until just set in the middle. Top with extra candy if desired.
Cool for 5 minutes on the baking sheet before transferring to a cooling rack. Cool completely before storing in an airtight container.
Keep the peanut butter cups in the freezer while making the cookie dough. This helps to keep the cups intact when folding into the dough.
When adding flour, mix until just incorporated. Overmixing can create a tough cookie.
Store cookies in an airtight container for 3-4 days.